Commit 54055344 authored by Brijesh Singh's avatar Brijesh Singh Committed by Borislav Petkov (AMD)
Browse files

x86/traps: Define RMP violation #PF error code 



Bit 31 in the page fault-error bit will be set when processor encounters
an RMP violation.

While at it, use the BIT() macro.

Signed-off-by: default avatarBrijesh Singh <brijesh.singh@amd.com>
Signed-off-by: default avatarMichael Roth <michael.roth@amd.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Acked-by: default avatarDave Hansen <dave.hansen@intel.com>
Link: https://lore.kernel.org/r/20240126041126.1927228-9-michael.roth@amd.com
parent 1f568d36

arch/x86/include/asm/trap_pf.h

+12 −8
Original line number Diff line number Diff line
@@ -2,6 +2,8 @@ 
#ifndef _ASM_X86_TRAP_PF_H

#define _ASM_X86_TRAP_PF_H



#include <linux/bits.h>



/*

 * Page fault error code bits:

 *
@@ -13,16 +15,18 @@ 
 *   bit 5 ==				1: protection keys block access

 *   bit 6 ==				1: shadow stack access fault

 *   bit 15 ==				1: SGX MMU page-fault

 *   bit 31 ==				1: fault was due to RMP violation

 */

enum x86_pf_error_code {

	X86_PF_PROT	=		1 << 0,

	X86_PF_WRITE	=		1 << 1,

	X86_PF_USER	=		1 << 2,

	X86_PF_RSVD	=		1 << 3,

	X86_PF_INSTR	=		1 << 4,

	X86_PF_PK	=		1 << 5,

	X86_PF_SHSTK	=		1 << 6,

	X86_PF_SGX	=		1 << 15,

	X86_PF_PROT	=		BIT(0),

	X86_PF_WRITE	=		BIT(1),

	X86_PF_USER	=		BIT(2),

	X86_PF_RSVD	=		BIT(3),

	X86_PF_INSTR	=		BIT(4),

	X86_PF_PK	=		BIT(5),

	X86_PF_SHSTK	=		BIT(6),

	X86_PF_SGX	=		BIT(15),

	X86_PF_RMP	=		BIT(31),

};



#endif /* _ASM_X86_TRAP_PF_H */

arch/x86/mm/fault.c

+1 −0
Original line number Diff line number Diff line
@@ -547,6 +547,7 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad 
		 !(error_code & X86_PF_PROT) ? "not-present page" :

		 (error_code & X86_PF_RSVD)  ? "reserved bit violation" :

		 (error_code & X86_PF_PK)    ? "protection keys violation" :

		 (error_code & X86_PF_RMP)   ? "RMP violation" :

					       "permissions violation");



	if (!(error_code & X86_PF_USER) && user_mode(regs)) {